Sesamol

Several other naturally occurring antioxidants have been identified in oils. Sesamol [533-31-3] (6) occurs as sesamoline [526-07-8], a glycoside, in sesame seed oil. FemUc acid [1135-24-6] (7) is found esterified to cycloartenol [469-38-5] in rice bran oil and to 3-sitosterol in com oil. Although it does not occur in oils, rosemary extract has also been found to contain powerful phenoHc antioxidants (12). 

Cinnamyl—sesamol ethers, eg (35), are useful as insect chemosterilants (111). 3,4-Methylenedioxyphenyl-3-halo-2-propynyl ethers (36, X = halogen) are synergists for carbamate insecticides (112). HaloaLkyl or haloalkenyl ethers, eg (37), show acaricidal and insect juvenile hormone activity (113). The first total synthesis of gibbereUic acid was from 2-methoxy-6-aLkoxyethyl-l,4-benzoquinone, a derivative of hydroxyhydroquinone (114). 

Oommachan, M., and S. S. Khan. Plants in aid of family planning programme. Sci Life 1981 1 64-66. Yoshida, M., and T. Kashimoto. Determination of sesamolin, sesamin and sesamol in sesame oil by high-performance liquid chromatography. Shokuhin Eiseigaku Zasshi 1982 23 142-148. 

Sesamum indicum L. Wu Ma (Sesame) (seed) Olein acid, linolein acid, pahnitine acid, stearin acid, myristic acid, sesamin, sesamol, pentosan, phytin, lecithin, choline, calcium oxalate, chlorogenic acid, vitamin A, vitamin B.49 A nutrient, laxative, hyperchlorhydria, a lenitive in scybalous constipation, as nutrient tonic in degenerative neuritis, neuroparalysis. 

The same strategy was successfully employed in the preparation of the natural product cicerfurane. The procedure started from 4-bromoresorcine and the sesamol-derived acetylene derivative in 3.59.75 One-pot acetyletion, cross-coupling and deprotection followed by spontaneous ring closure led to... 

Hirose, M., Fukushima, S., Shirai, T., Hasegawa, R., Kato, T., Tanaka, H., Asakawa, E. Ito, N. (1990) Stomach carcinogeiucity of caffeic acid, sesamol and catechol in rats and mice. Jpn. 

Hydroxy- J-qidnones Silver oxide oxidizes derivatives of methyl sesamol 1 to quinones of this type (equation 1). 

SYNTHESIS A solution of 11.5 g pellet KOH (85%) in 75 mL EtOH was treated with 25 g sesamol followed by 27 g methyl iodide. This was brought to reflux on the steam bath. Salt formation was apparent in 20 min, and refluxing was maintained for atotal of 4 h. The solvent was removed under vacuum, and residue poured into 400 mL H,0. This was acidified with HC1 and extracted with 3x150 mL... 

The remaining MMDA-analogue that has been prepared, is the 2,3,6-isomer. The flow diagram started with sesamol (3,4-methylenedioxyphenol) which was methylated with methyl iodide, converted to the aldehyde using butyllithium and N-methylformanilide (putting the new group directly between the two oxygen... 

Beak used this method in a synthesis of (-)-paroxetine 97 (Paxil or Seroxat), a selective serotonin reuptake inhibitor.9 Lithiation of 92 with n-BuLi-(-)-sparteine and addition of the product 93 to the nitroalkene 94 yields the protected Z-enamine 95, as usual for reactions of lithiated allylamides, in >94% ee. Hydrolysis and reduction of the product, followed by mesylation and cyclisation gave the fnms-substituted piperidine 96. Displacement of the hydroxyl group by sesamol yielded (-)-paroxetine 97. 

Heterocycles of this type occur widely. The benzo[l,3]dioxole ring system is often found in natural products and their degradation products, e.g., sesamol 38 lipoic acid 39 is a naturally occurring 1,2-dithiolane derivative. The 1,3-dithiolanes 40 are commonly known as 1,3-dithioacetals and have been extensively used in carbonyl group chemistry. In the absence of cyclic conjugation, ring sulfur atoms can readily exist in higher oxidation states as, for example, in the oxathiole S, -dioxide 41. 1,3,2-Dioxathiolane A-oxides 42 (cyclic sulfites) and 1,3,2-dioxathiolane A,A-dioxides (cyclic sulfates) are useful as synthetic equivalents of epoxides. 

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